In college I had a 90GB OCZ Vertex, or maybe it was a Vertex 2.

It would suddenly become blank. You have an OS and some data today, and tomorrow you wake up and everything claims it is empty. It would still work, though. You could still install a new OS and keep going, and it would work until next time.

What a friendly surprise on exam week.

Sold it to a friend for really cheap with a warning about what had been happening. It surprise wiped itself for him too.